Mesenchymal Stem Cell Secretome for Cardiac Regeneration: Opportunity for Cell-Free Therapy.

Cell-free therapy is gaining increasing interest among researchers as an alternative to mesenchymal stem/stromal cell (MSC) therapy. Since the therapeutic effects of MSCs rely predominantly on their paracrine activity, the use of their secretome as a therapeutic agent in broadly defined regenerative medicine, including cardiac regeneration, appears to be a rational approach. In this review, we discuss recent studies that employed secretomes derived from various types of MSCs in cardiomyocyte regeneration following myocardial infarction (MI). Special attention is given to the protein components of the secretome, which may drive tissue repair, and methods of priming the MSC to achieve secretome composition tailored for heart regeneration. Finally, we summarize recent preclinical findings on the effects of MSC secretomes on cardiomyocyte regeneration.